The invention relates to an arrangement for generating digital signals for a transmission system, more specifically control signals recurring, in essence, in a predeterminable time frame.
Such an arrangement is necessary, for example, in transmitters and receivers (radio sets) for the present Pan-European mobile radio system. In this mobile radio system speech signals are transmitted in digitized form together with other digital signals in a time-division multiple access method (TDMA). This requires a precise time timing control of various functions. A multiplicity of control signals is necessary for this purpose, which signals generally exhibit a periodic variation, i.e. are cyclically recurrent in a predeterminable time frame. In addition, these timing control signals should also be individually controllable in dependence on a large number of different operating requirements. The timing control signals may be derived from the signal of a central clock generator designated as a timer. This clock generator is in essence based on a counter which triggers an interrupt function of the processor of the radio set when a predetermined value is reached or exceeded and/or directly affects external control signals. If a large number of timing control signals are generated in this manner with a rather high time-dependent resolution, the processor is loaded very heavily. Another possibility consists of generating the timing control signals by means of specific switch mechanisms. The timing control signals are then predetermined, so that considerable restrictions arise with respect to the flexibility when these switch mechanisms are used, for example, when individual control signals are changed.